1、Designation: C844 04 (Reapproved 2010)C844 15Standard Specification forApplication of Gypsum Base to ReceiveGypsum Veneer Plaster1This standard is issued under the fixed designation C844; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This specificat
3、ion covers the minimum requirements for, and methods of, application of gypsum veneer base for gypsumveneer plasters.1.2 Gypsum veneer base shall not be used as a base for direct adhesive application of ceramic, metal, or plastic tile in areasexposed to abnormal moisture or humidity or temperature.1
4、.3 Details of construction for a specific assembly to achieve the required fire resistance shall be obtained from reports offire-resistance tests, engineering evaluations, or listings from recognized fire testing laboratories.1.4 Where a specific degree of sound control is required for veneer plaste
5、r assemblies and constructions, details of constructionshall be in accordance with official reports of tests conducted in recognized sound testing laboratories in accordance with theapplicable sound tests, Test MethodMethods C423, Test Method E90, or Test Method E492.1.5 Where this specification is
6、more stringent (size or thickness of framing; spacing of fasteners) than the fire-rated construction,this specification shall govern; otherwise, the construction described in the fire test report shall govern.1.6 Unheated spaces above gypsum veneer base ceilings shall be properly ventilated (see App
7、endix X3).1.7 The values stated in inch-pound units are to be regarded as the standard. The SI (metric) values given in parentheses areapproximate and are provided for information purposes only.1.8 The text of this standard references notes and footnotes which provide explanatory material. These not
8、es and footnotes(excluding those in tables and figures) shall not be considered as requirements of the standard.2. Referenced Documents2.1 ASTM Standards:2C11 Terminology Relating to Gypsum and Related Building Materials and SystemsC423 Test Method for Sound Absorption and Sound Absorption Coefficie
9、nts by the Reverberation Room MethodC514 Specification for Nails for the Application of Gypsum BoardC587 Specification for Gypsum Veneer PlasterC588/C588M Specification for Gypsum Base for Veneer Plasters (Withdrawn 2005)3C754 Specification for Installation of Steel Framing Members to Receive Screw-
10、Attached Gypsum Panel ProductsC954 Specification for Steel Drill Screws for the Application of Gypsum Panel Products or Metal Plaster Bases to Steel Studsfrom 0.033 in. (0.84 mm) to 0.112 in. (2.84 mm) in ThicknessC955 Specification for Load-Bearing (Transverse and Axial) Steel Studs, Runners (Track
11、s), and Bracing or Bridging for ScrewApplication of Gypsum Panel Products and Metal Plaster BasesC1002 Specification for Steel Self-Piercing Tapping Screws for Application of Gypsum Panel Products or Metal Plaster Basesto Wood Studs or Steel StudsC1007 Specification for Installation of Load Bearing
12、(Transverse and Axial) Steel Studs and Related Accessories1 This specification is under the jurisdiction of ASTM Committee C11 on Gypsum and Related Building Materials and Systems and is the direct responsibility ofSubcommittee C11.03 on Specifications for the Application of Gypsum and Other Product
13、s in Assemblies.Current edition approved May 15, 2010April 1, 2015. Published September 2010April 2015. Originally approved in 1978. Last previous edition approved in 20042010as C844C844 04 (2010).04. DOI: 10.1520/C0844-04R10.10.1520/C0844-15.2 For referencedASTM standards, visit theASTM website, ww
14、w.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of wh
15、at changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered th
16、e official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1C1047 Specification for Accessories for Gypsum Wallboard and Gypsum Veneer BaseC1396/C1396M Specification for Gypsum BoardC1546 Guide for Installation of Gypsum Produ
17、cts in Concealed Radiant Ceiling Heating SystemsE90 Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and ElementsE492 Test Method for Laboratory Measurement of Impact Sound Transmission Through Floor-Ceiling Assemblies Using theTapping Machine2.2 Amer
18、ican Softwood Lumber Standard:PS20 American Softwood Lumber Standard33. Terminology3.1 DefinitionsDefinitions:Definitions3.1.1 Definitions shall be in accordance with Terminology C11. shall be in accordance with Terminology C11.3.2 Definitions of Terms Specific to This Standard:3.2.1 base plyply, nf
19、irst ply of gypsum base in multiple ply application.3.2.2 face plyouter or visible layer of gypsum base in multiple ply application.3.2.2 face ply, nouter or visible layer of gypsum base in multiple ply application.3.2.3 fastener, nnails, screws, or staples used for the application of the gypsum bas
20、e or backing board.3.2.4 framing member, nthat portion of the framing, furring, blocking, etc., and so forth, to which the gypsum base is attached.Unless otherwise specified, the surface to which abutting edges or ends are attached shall be not less than 112 in. (38 mm) widefor wood members, not les
21、s than 114 in. (32 mm) (32 mm) wide for steel members, and not less than 6 in. (152 mm) (152 mm)wide for gypsum studs. For internal corners or angles, the bearing surface shall be not less than 34 in. (19 mm).(19 mm).3.2.5 parallel application, ngypsum base application where the gypsum base edge is
22、applied parallel to the framing members.3.2.6 perpendicular application, ngypsum base application where the gypsum base edge is applied at right angles to theframing members.4. Materials4.1 Materials shall conform to the respective specifications and standards and to the requirements specified herei
23、n.4.2 Gypsum Base for Veneer Plasters (hereinafter referred to as “gypsum base”)Specification C588/C588MC1396/C1396M.4.3 Gypsum Backing Board or CoreboardBoardSpecification C442C1396/C1396M.4.4 Special Fire-Retardant Gypsum BaseSpecification C588/C588MC1396/C1396M, Type X.4.5 Foil-Backed Gypsum Base
24、Specification C588/C588MC1396/C1396M.4.6 Gypsum Veneer PlasterSpecification C587.4.7 NailsSpecification C514.4.8 Screws:4.8.1 Non-load bearing steelSpecification C1002.4.8.2 Load bearing steelSpecification C954.4.9 StaplesNo. 16 USS gage 0.063 in. (1.6-mm) gauge 0.063-in. (1.6 mm) flattened galvaniz
25、ed wire with 716-in.(11.1-mm)(11.1 mm) wide-crown minimum outside measure and divergent points. Staples shall be used only for the base ply oftwo-ply application over wood framing.4.10 Steel Framing, Non-load bearingSpecification C645 for the specified design criteria.4.11 AccessoriesSpecification C
26、1047.4.12 Adhesive: AdhesiveFor application of gypsum base to steel framing, the adhesive shall be as recommended by themanufacturer of the gypsum base.4.13 Steel Framing Load BearingSpecification C955.4.14 Wood FramingAmerican Lumber Softwood Standard PS20.5. Delivery of Materials5.1 All materials
27、shall be delivered in the original packages, containers, or bundles bearing the brand name and manufacturer(or supplier) identification.3 Available from National Institute of Standards and Technology (NIST), 100 Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http:/www.nist.gov.C844 1526. Shippi
28、ng, Handling and Storage6.1 Gypsum board shall be shipped so as to be kept dry.6.2 Gypsum board shall be stored so as to be kept dry, preferably inside a building, under a roof. Gypsum board shall be neatlystacked flat with care taken to prevent sagging or damage to edges, ends, and surfaces.6.3 Whe
29、re necessary to store gypsum board outside, it shall be stacked flat, off the ground, supported on a level platform, andfully protected from weather and direct sunlight exposure.6.4 Prior to application, the building exterior shall be so enclosed to protect the gypsum base from exposure to weather a
30、nddirect sunlight.NOTE 1The bond of alkaline veneer plaster to gypsum base will be impaired if the base is exposed to direct light or sunlight for extended periods.7. Environmental Conditions7.1 Application of Gypsum Base and AdhesivesA room temperature of not less than 40 F (4 C) 40F (4C) shall bem
31、aintained during application of gypsum base except when adhesive is used for the attachment of gypsum base. For the bondingof adhesive, a room temperature of not less than 50 F (10 C) 50F (10C) shall be maintained for 48 h prior to application andcontinuously thereafter until adhesive is completely
32、dry. When a temporary heat source is used, the temperature shall not exceed95 F (35 C) 95F (35C) in any room or area.Adequate ventilation shall be maintained in the working area during the applicationand adhesive curing process.8. Application of Gypsum Base8.1 General Requirements:8.1.1 Installation
33、 of steel framing shall be in accordance with applicable Specifications C754 or C1007 except where supersededby requirements of Table 1.NOTE 2For general wood framing requirements, see Appendix X2.8.1.2 Method of CuttingThe gypsum base shall be cut by scoring and breaking or by sawing, working from
34、the face side.When cutting by scoring, the face shall be cut with a knife or other suitable tool and the gypsum base snapped back away fromthe cut face. The back shall be broken by snapping the gypsum base in the reverse direction, or by cutting with a knife or othersuitable tool.8.1.3 All cut edges
35、 and ends of the gypsum base shall be smoothed to obtain neat jointing. Cut-outs for pipes, fixtures, or othersmall openings on the face and back of the base shall be scribed in outline before removing or cut out with a saw or other suitabletool. The gypsum base shall be scribed where it meets proje
36、cting surfaces. Base shall be brought lightly into contact with adjacentpanels but not forced into place. Abutting ends and edges shall fit neatly.8.1.4 When gypsum base is to be applied to both ceiling and walls, the base shall be applied to the ceiling and then to the walls.8.2 Fastening, Mechanic
37、al:8.2.1 The gypsum base shall be held in firm contact with the underlying support while driving any fastener.8.2.2 Fastener application shall proceed from the center of the field of the gypsum base to the ends and edges or shall beginalong one edge and proceed toward the other edge.8.2.3 Except whe
38、re required for fire rating, structural performance, or other special considerations, fastening to top or bottomplates shall not be required.8.2.4 Fasteners shall be spaced not less than 38 in. (9.5 mm) from the edges and ends of the gypsum base. Fasteners used atedges or at base ends in horizontal
39、application shall not be more than 1 in. from edges or ends.TABLE 1 Maximum Framing SpacingSingle-ply Base (Thickness), in. (mm) Application to Framing Maximum On Center Spacing ofFraming, in. (mm)Ceilings:12 (12.7)12 (12.7)A58 (15.9)Bparallelperpendicularperpendicular16 (406)24 (610)24 (610)Sidewal
40、ls:38 (9.5)C perpendicular 16 (406)12 (12.7) parallel 16 (406)12 (12.7)A perpendicular 24 (610)58 (15.9)B parallel or perpendicular 24 (610)A 12-in. (12.7-mm)(12.7 mm) gypsum base applied perpendicular on 24-in. (610-mm)(610 mm) on centers framing shall be considered to be minimum construction.B For
41、 58-in. (15.9-mm)(15.9 mm) base, perpendicular on ceilings and either perpendicular or parallel on sidewalls at 24-in. (610-mm)(610 mm) on centers spacing, onlytwo-component veneer plaster or special joint reinforcement, as recommended by the gypsum veneer plaster manufacturer, shall be used.C 38-in
42、. (9.5-mm)(9.5 mm) gypsum base shall be used over wood framing with two-component veneer plaster systems only.C844 1538.2.5 Nails and screws shall be driven to a point flush with the gypsum base surface without breaking the surface paper ordamaging the surrounding gypsum core and without stripping t
43、he framing member around the screws.8.2.6 Staples shall be driven so that both legs penetrate the support member and the crown bears tightly against the backingboard, but does not cut into the face paper. The staple shall be driven with the crown parallel to framing members. Staples shallbe used onl
44、y for the first ply in two-ply gypsum base systems.8.2.7 Penetration of mechanical fasteners into supporting framing members shall be not less than:Nails Screws StaplesWood: 78 in. (22 mm) 58 in. (15 mm) 58 in. (15 mm), each legSteel: . 38 in. (9 mm) .8.3 Control JointsJoints:8.3.1 Control joints sh
45、all be installed in ceilings more than 2500 ft2 (232 m2) in area that are constructed with perimeter relief.The distance between control joints shall be not more than 50 ft (15 m) in either direction.8.3.2 Ceilings of more than 900 ft2 (85 m2) in area constructed without perimeter relief shall have
46、control joints installed withspacing not to exceed 30 ft (9 m) in either direction.8.3.3 Control joints shall be installed where ceiling framing or furring changes direction or where construction joints occur inthe base building construction. In partitions, walls, or wall furring, the distance betwe
47、en control joints shall be not more than 30ft (9 m).8.3.4 A ceiling height door frame, installed in accordance with the spacing requirements set forth in 8.3, functions as a controljoint.9. Application of Single-Ply Gypsum Base9.1 The maximum spacing of framing members for single-ply gypsum base con
48、struction shall be not more than those shownin Table 1.9.2 In single-ply installation, all ends and edges of gypsum base shall occur over framing members or other solid backing exceptwhere treated joints occur at right angles to framing or furring members.9.3 Joints on opposite sides of a partition
49、shall be arranged to occur on different framing members.9.4 Fasteners (Single Ply Application):9.4.1 Nail SpacingSpace nails a maximum of 7 in. (178 mm) (178 mm) on centers on the ceiling and a maximum of 8 in. (203mm) (203 mm) on centers on the walls.9.4.2 Double NailingNails shall be spaced as shown in Fig. 1 and applied as follows:9.4.2.1 Starting at the center of the base, nails shown as solid dots shall be applied by row starting with row 1, then rows 2 and2A, 3 and 3A, 4 and 4A. Base shall be kept tight again
